Quoted from pinstor12:
Metal apron and metal playfield support rails on 07. Plastic apron and peg supports after 07.
Quoted from sammiesguys:
Mine is from April 2008 and has a metal apron and playfield support rails.
My Dec. 21, 2009 build also has a metal apron and under PF support rails.
Bought the game from original owner who never mentioned these items with the other mods he installed...so did these changes come in '10 perhaps?